Internal combustion engine



March 1940. s. G. KITZEMAN INTERNAL COMBUSTION ENGINE 5 Sheds-Sheet 1 Filed Nov. 4, 1936 March 19, 1940.

cs. G. KITZEMAN 2,194,022

INTERNAL COMBUSTION ENGINE Filed Nov. 4; 1936 3 Sheets-Sheet 2 Zwentor- Geo/ye @Zzenzmv, 1 GM #a, ws.

March 19, 1940. G. e. KITZEMAN 2,194,022

INTERNAL COMBUSTION ENGINE Filed Nov. 4, 1936 3 Sheets-Sheet I5 Patented Mar. 19, 1940 UNITED STATES PATENT OFFICE 19 Claims.

This invention relates to internal combustion engines or other devices having a crank shaft, pistons andconnectlng rods, and operated by or upon fluid pressure, and more particularly to providing greater mechanical efllciency, greater thermal efficiency and more effective torque in such devices. r

One of the objects of my invention is the production of greater mechanical efliciency in devices of the class referred to, as well as greater thermal efilciency and more effective torque in a given unit of time.

A further object is to provide in a device of the class referred to a plurality of pistons, one

ll reciprocating within the other, and two connecting rods respectively connected to said pistons, said connecting rods being so connected at their lower ends to the crank or cranks of the crank shaft that the lower end of one of said connecting rods will pass beyond dead center ahead of the lower end of the other of said connecting rods.

Another object is the provision of a device of the class referred to in which the vertical axis 28 of the cylinder may be offset laterally from a vertical line passing through the axis of the crank shaft, and the parts arranged so that said offset takes effect largely in the first period of the first quadrant beyond the dead center in the direc- 30 tion of rotation of the crank.

Still another object is the provision of a device of the class referred to in which the cylinder is so offset and the parts so arranged that said offset takes effect early in the first quadrant at 38 and beyond the top dead center in the direction of rotation of the crank, supplemented by a co-oflset piston and a re-offset cylinder.

Another object is to provide means whereby the thrust shocks incidental to change of direc- 40 tion of movement of the pistons and contiguous reciprocating parts, are largely cancelled by counteraction, coaction and interaction within a fractional unit of time relatively to each other.

Still another object is to provide means whereby the efliciency in torque in a mechanism operating reciprocally is definitely increased by the equivalent of a. shift in axis relative to centers of pressure, by co-ofiset pistons and offset and/or re-offset cylinders, this shift taking effect immediately plus and/or minus dead centers, and progressively doing so during the first part of the power stroke and alternately thereafter in an internal combustion engine, air compressor, suction pump or the like.

A still further object is to secure more effective pressure by a carry-over of volume at upper dead center within a brief unit of time and without added input work, this carry-over on coinpression taking effect at the sufficiently advanced crank angle in the most effective period of the I expansion and at the beginning of the power stroke in an internalcombustion engine.

Anotherobject is to create more favorable thermal conditions by a definite kind of flame propagation through turbulence of the fuel mix- 10 ture both before and during inflammation, and to provide for better scouring of the cylinder walls and for longer and more complete coverage of the cooling area of the cylinder walls in the combustion chamber during inflammation and II eilipansion in internal combustion engines or the li e.

A still further object is to provide for the more rapid removal of heat from the reciprocating parts subjected to the heat of combustion in an 20 internal combustion engine through redistribution of central piston'area and cross-section from the1 hottest toward the coolest side of the cylinder wa ls.

Another object is to provide means for,im- 25 proving the scavenging of the products of combustion,from within the cylinder of an internal combustion engine or the like by mechanically agitating the contents of the combustion chamber at the end of the exhaust stroke by piston interaction.

' A still further object is to provide an internal combustion engine or the like having increased power and at the same time less fuel consumption as well as less weight in engine structure per 35 I pound per power unit.

Another object is to. provide means whereby cylinders of small bore may be ofl'set, co-oflset and/or re-offset in order to direct the effective forces past dead centers and thereby increase 40 the torque and efliciency.

A further object of this invention is to convert in devices of the class referred to the relatively ineflicient near dead center periods of time into useful periods of time, and thus to increase 45 the net power output of the'available pressure.

Other objects, advantages and capabilities inherent in my invention will later more fully appear.

My invention further resides in the combination, construction and arrangement of parts illustrated in the accompanying drawings, and while I have shown therein preferred embodiments I wish it understood that the same are susceptible 55 of modification and change without departing from the spirit of my invention.

In the drawings:

Fig. 1 is a vertical transverse section through a portion of an internal combustion engine embodying my invention, parts being broken away for convenience.

Fig. 2 is a vertical section taken at right angles to the section of Fig. 1 substantially on the line 2-2, showing some of the parts in elevation and parts being broken away for convenience.

Fig. 3 is a perspective view of the double or composite connecting rod, which acts as a unit in cooperation with the outer piston.

Fig. 4 is a fragmentary detail plan view of thecrank pins, cranks and adjacent portions of the crank shaft.

Fig. 5 is a diagrammatic side view showing the relation between the pistons, the connecting rods and the crank pins Just prior to the time when the two crank pins are at the eflective dead center.

Fig. 6 is a view similar to Fig. 5 but showing the parts and pistons with the two crank pins on eflective dead center.

Fig. '7 is a view similar to Fig. 8 but showing the parts and pistons with the two crank pins just past dead center a slight distance.

Fig. 8 is a view similar to Fig. 'I with the crank pins having advanced a somewhat greater distance beyond dead center.

Fig. 9 is a view similar to Fig. 8, showing the crank pins having advanced beyond their position shown in Fig. 6.

Fig. 10 is a view similar to Fig. 9 but showing the crank pins as having advanced and showing the two pistons on the upstroke.

Fig. 11 is a vertical transverse section substantially on the line llli of Fig. 12 through a modification, comprising two separate cylinders in which the cylinders are offset relative to each other and the angularity of the pistons and connecting rods so arranged as to accomplish in a plurality of cylinders some of the same results as are accomplished in the preferred form having one piston reciprocal within the other piston.

Fig. 12 is a vertical section taken through one of the cylinders at right angles to the section shown in Fig. 11, but showing the piston, connecting rods and crank pins in elevation.

Referring in detail to the accompanying drawings, I have shown my invention therein as applied to an internal combustion engine of the four cycle type, but wish it understood that my invention is also applicable to other uses such as with a suction pump, a compressor, a two cycle internal combustion engine and the like. It is, therefore, to be understood that my invention has been shown as applied to a four cycle gas engine merely for illustrative purposes and not as limiting my invention to use in only this form of mechanism.

In Fig. 1 the internal combustion engine in which my invention for convenience is illustrated, comprises a cylinder I having the usual water Jacket space 2, interior cylinder walls 3, crank case 4 (shown partly broken away), combustion chamber 5, spark plugs l, exhaust valves I (the inlet valve not being shown in Fig. 1), cylinder head I having water jacket spaces to communicate in the usual manner with the water jacket spaces in the cylinder block, and other parts which go to make a complete internal combustion engine, but some 01 which parts are omitted for convenience and because they have nothing to do with the present invention.

The crank shait I is formed with the spaced crank arms Ill and II, there being provided between these two crank arms crank pins l2, l8 and I4, crank pin it being offset from crank pins l2 and I l, the importance or which oii'set will be later more fully explained. Recipmcally mounted within cylinder walls I is the outer piston ll provided with the usual piston rings ll. Formed within the outer piston II is the angularly extending bore II, the angle formed between one of the longitudinal elements 01' this bore and the vertical walls of the piston ll being shown as approximately 10. This angle may be varied as desired within permissible limits. Re-

:ciprocally mounted within bore I! of outer piston II is the interior piston it. which is provided with the usual piston rings I, so positioned as not to become exposed during operation. Pivotally connected by wrist pin 2| to the interior piston II is what for convenience will be herein termed the middle connecting rod 2|, which connecting rod carries at its lower end with appropriate cooperating parts the bearing member 22, which is mounted upon crank pin II, this bearing member being completed by the cap portion 24 suitably connected to bearing 23 bybolts 26 orthe like. Thisbearingwillbeprovided with suitable Babbitt metal, bronze or other bushings as may be desired, for operation upon crank pin I! in accordance with well settled practice.

Pivotally connected to the outer piston II are two connecting rods which are shown yoked together to form a composite connecting rod (Fig. 3), this composite connecting rod being identifled generally as C and comprising the two individual connecting rods 2| and 2' secured together by the bolts 21 and 22 so that they will work together as a unit. Under some circumstances, however, these two connecting rods may not be yoked together but may be separate except as they are both connected at their top to the outer piston, and at their bottom to the aligned crank pins l2 and I4.

At the upper end of connecting rod 2| is a laterally extending sleeve 2., and at the upper end of connecting rod 26 is a similar sleeve 80 extending laterally in a direction opposite to that 01' sleeve 28, the'opening through these two sleeves being in longitudinal alignment to receive the wrist pin 2i as shown in Fig. 2, there being also provided a suitable bushing 22 to fill the space between the inner faces 01' the upper ends of these two connecting rods for additional strength and alignment.

As seen in Fig. l, the middle connecting rod 2| is provided near its upper end with an enlarged portion in which is formed an appropriately shaped opening 22 to accommodate movement of the bushing 22 01 wrist pin II. In other words, this opening 22 permits independent motion of the two pistons, the wrist pin SI and connecting rod 2!, and without any interference between these parts. If desired wrist pin ll maybe omitted and trunnions 2| and II function as the wrist pin, in which case the composite unit construction 0, shown in Fig. 3, would be used, and the opening 32 in connecting rod 2| omitted. The lower or skirt portion of the inner piston is formed with two diametrically opposite elongated slots 24, 2|, in which slots the laterally extending sleeves or trunnions 22 and "at the upper and or connecting rod 0 28 of the composite connecting rod C are pro.-

vided with the bearing members 36, 81, respectively, which in turn are respectively provided with the bearing caps or complemental half members 38, 39 held in place by suitable bolts 0, II. The bearing members 36 and 31 of the composite outer crank arm C engage respectively with the crank pins i4 and I2 shown in Fig. 4. Thes; parts are shown in assembled relation in Fig.

As is understood, the crank shaft 8 will be mounted in suitable bearings (not shown) as is customary in this type of mechanism. In addition to the inner piston being reciprocally mounted at an angle with relation to the exterior piston, I may also offset the cylinder I to the right (as shown in Fig. l) with relation to a vertical plane passing through the axis of the crank shaft by an amount indicated in Fig. 1 at 0. In other words, the vertical axis of the cylinder l falls a distance 0 to the right of the vertical plane passing through the axis of the crank shaft. The amount of this offset may vary or may be laterally inclined (as suggested by the two lines :2, a: in Fig. 1) without departing from the spirit of my invention, and while in some cases this off:- set is of great importance I may in some instances entirely omit this offset and/or this angularity ofthe cylinder while still retaining the angular position of the interior piston with relation to the exterior piston. While the benefits are greater with the use of both the offset cylinder as well as the angular relation between the pistons, the advantages derived from the angularly positioned piston and spaced apart connecting rods are sufficient to be worth while even without the ofiset cylinder, although the latter in most cases is preferred.

In the preferred form as shown in Figs. 1 to 10, inclusive, it is pointed out that the lower end of the middle connecting rod 2| is mounted upon crank pin IS. The direction of rotation of the crank shaft and crank pins is in the direction of the arrow shown in Fig. 1. As the lower ends of the two exterior connecting rods 25 and 26 are mounted respectively upon crank pins l4 and II, it will be seen in Fig. 1 that the middle connecting rod 2! is the leading connecting rod and the composite connecting rod C (made up of connecting rods 25" and 2,) is the trailing connecting rod or connecting rods. This specific connection of connecting rods with crank pins just described, refers particularly to the utilization of my invention in an internal combustion engine. When my invention is applied to other mechanisms such as suction pumps, compressors and the like, the direction of rotation may be reversed and the mounting of the connecting rods may also be reversed, for the reason that the operations and functions in such devices frequently are reversed as compared with those of an internal combustion engine.

It is also to be noted in the preferred form shown in Figs. 1 to 10, inclusive, that the middle connecting rod 2| is of greater lengththan the outer connecting rods 25 and 26, which latter two connecting rods as stated above form the composite connecting rod C. Also it is to be noted that the middle or longer connecting rod II is connected to the inner piston. This arrangement prevents conflict of wrist pins and also performs the further important function of converting what would otherwise be useless dead center motion into effective motion when the crank pins are passing through dead center. This latter function of the unequal length connecting rods is partly effected by the fact that the lower 7 end of the longer connecting rod moves through a flatter arc than the lower end of the shorter connecting rods, and consequently the eflect on volume in the combustion chamber is such that the pressure is more effective when the lower ends of the connecting rods pass the vertical dead center line.

As stated above the middle connecting rod II is longer and makes at its lower end a flatter are. This taken together with its beingpivoted at the upper end in the center of the inner piston, which center lies to the left (Fig. 1) of the vertical axis of the cylinder on the up or compression stroke, will cause this piston to pass over top dead center first before compression has been fully completed, owing to the lag of the exterior piston. When the position is reached as shown in Fig. 6, the out and downward movement of the leading crank pin 13 and its connecting rod 2| and the interior piston I8 will act 'to produce a quicker get-away from dead center, with a volume increase of the combustion chamber approximately equal to that which would obtain when a single piston of the conventional type is used with a centrally pivotedconnecting rod of a length equal to the mean length of the long and short connectingrods of the present invention and a single centrally located crank pin, this taking place while the trailing crank pins 12 and H are passing through their upper limit of movement at a pressure decreasing and, therefore, not involving additional work on compression of the outer piston but simply sustaining or carrying over the compression it will have producedwhen the inner piston has passed over the dead center to the same distance that the outer piston lags behind dead center.

This intereaction between'the two pistons at upper dead center with their working faces inclined toward the hot side (Figs. 1 and 5 to 10 inclusive), creates a greater turbulence in the combustion chamber during the usual period of inflammation and expansion of the compressed fuel. This turbulence being of a kind most favorable to flame propagation, provides a better mechanical mixing and on the up or exhaust stroke a better scavenging of the products of combustion. At the same time the outer piston being delayedat upper dead center longer, provides for a coverage of the cooling walls during the burning period and during a part of the expansion period, and also has the effect of scouring the usual film from the cooling walls that accumulates prior to and in the first stages of combustion in this period. There is a further advantage in that the inner piston I8 leaves the scene ofthis action first at an accelerated speed, carrying most of its heat derived from the inflammation period away from the center of area and particularly away from the hottest side of the combustion chamber, this being the side where usually the exhaust valves and exhaust manifolds are situated. This directs the heat by conduction to the cooler side of the cylinder and leaves a smaller cross-section of the outer piston, lying nearest the hotter side of the cylinder, to be cooled within the same unit time that would prevail in a single piston where the center heat would have to be radially conducted equally in all directions over a longer period of time and towards unequal cooling temperatures of the cooling media as above stated, causing distortion of the piston.

when the parts are in the position shown in Figs. 1 and 8, it is apparent that since the wrist pin ll connects the composite connecting rod 0 to the outer piston ll near the vertical center of the latter, and this being also near the vertical center of the off-set cylinder I unless the latter is re-oifset, the lower ends of this composite connecting rod on its crank pin bearings i2, M are still minus the dead center line E (Fig. 1). This equilibrated position or top dead center would prevail at this point only so long as connecting rods C and 2| would remain stationary and form equal angles with the dead center line, and the pressure receiving faces of pistons II and it would be substantially in longitudinal alignment. soon, however, as this equilibrium is broken, inside piston It will move at an angle to the line E (Fig. 1) which passes through the axis of crank shaft 9, and acting through its connecting rod 2| and crank pin I 3 upon crank arms II and H and reacting upon crank pins l2, ll the outer piston I! will move up and down by its connecting rod C. When the lower end of the composite connecting rod C has passed beyond this upper dead center, or point of equilibrium referred to above, in the direction of the arrow in Fig. 1, it will be moving in a direction toward that in which the cylinder is offset, which movement for convenience will be referred to hereinafter as moving into the oii'set, this term applying, however, only after the two sets of crank pins have simultaneously passed through the upper effective dead center. In other words,. when said lower end of the composite connecting rod C and the crank pins l2 and I4 have passed beyond said effective upper dead center they are passing into the held of eccentric force due to the ofiset cylinder and disproportionate pressure area of working face of piston II, Fig. 1, as well as to the later timing in respect to coincidence of crank arm leverage relative to the fulcrum at the center .of the crank shaft 8, Figs. 1, 2, 4. This operative combination is further augmented by the coaction of the dissimilar, angular and linear movement of innerpiston l8 (Figs. 1, 5 to 10, inelusive).

The practical effect of these conditions is the same as though the axis of the crank shaft had been shifted to the left in Fig. 1 to shift the axis of thecrank shaft as regards eflective pressure, and thus to convert ineflicient dead center period of time and motion into more effective time and motion because of utilizing the most favorable crank arms and connecting rod angles coincident with the most favorable volumetric conditionsprevailing in the combustion chamber.

Now, referring to Figs. 1, 2, 6, 11 and 12, these show dead center positions when the tops or working faces of the pistons are of equal areas. The mean of the combined centers of pressure is on a line passing through the center of crank shaft 8 and midway between crank pins l2 and it, directly into the center of the combined working faces of the pistons. .The center of the upper end of the cylinder bore is offset as explained above, and the angular positions of the connecting rods are correspondingly oifset. Therefore, the center line E above the crank shaft is to the right of the vertical line L, so that when the crank arms II and II move approximately 10 in their normal course, crank pins I2 and M will be more nearly under the center of pressure of the cylinder offset as well as under the center of pressure of piston ll, while simultaneously the crank pin it and with it connecting rod 2| will have moved approximately 10 and at the same time will have moved downwardly a proportionate distancewith relation to line E. Connecting rod II is thus seen to be moving into the offset as aforesaid as well as shifting pivot 20, Fig. 1, laterally, supplementary to the movement above defined.

I prefer under certain circumstances, with respect to the hereinbefore stated equally distributed areas or the evenly apportioned pistons l5 and I8 shown in Figs. 1, 2 and 6, to give a preponderance in area to the inner piston ll shown in Fig. 1 and to piston It, the latter being the modiiied combination shown in Figs. 11 and 12. In the form of Figs. 11 and 12 this may be accomplished by providing different size bores in the two cylinders. This preponderance in area when transposed into circumferential value with relation to movement of the crank pin and angularity of connecting rods at dead center should not exceed the pressure equivalent of the oflset of cylinders as aforesaid.

The eflect of this reapportionment of area between the inner and outer pistons l5 and II respectively, would be to shift dead center to the left of the line E shown in Fig. 1 toward line L, leaving the connecting rods slightly askew angularly relative to each other at dead center, more nearly conforming to the vertical line L now coming midway between crank pins l2 and I3 respectively. The practical effect of this reapportionment is to lengthen the power stroke in the first quarter by beginning earlier, and accentuating the cylinder ofiset.

Another feature of my invention is to lessen the thrust shocks that ordinarily arise at the ends of the stroke when the direction of movement of the pistons changes. In my improved mechanism I have broken up these thrust shocks and as a result have correspondingly minimized their intensity. This will be understood more clearly by an inspection of Fig. 1, in which it be seen that the inner piston reaches its upper limit of travel ahead of the outer piston, and when the latter reaches its upper limit of travel the inner piston is well on its way down. It is thus seen that the thrust shock is broken up and very greatly lessened, which lessening is further assisted by the relative oblique angularity between the inner and outer pistons respecting the distinct moments of inertia in the form shown in Figs. 1 and 2. This effect will also be accomplished in some degree for more or less similar reasons in the modified form shown in Figs. 11 and 12.

In Figs. 11 and 12 I have shown a modified form of my invention applicable to cylinders of smaller diameters than could be accommodated by the form shown in Figs. 1 and 2, which latter form, as will be readily understood, due to contact of the connecting rods with the bottom end of the cylinder walls, has its limitations as to diameter. The form shown in Figs. 11 and 12 is adapted to smaller diameters of cylinder and disproportionately longer thrusts, but in engines having a cylinder diameter suiilciently large to utilize the form shown in forms 1 and 2 I prefer this form, for the reason that with larger diameter cylinders in the form shown in Figs. 11 and 12 there will be a possible excessive spacing betweenthe respective lower ends of the connecting rods. However, as is obvious, either form of my invention disclosed herein may be used as desired.

In the form shown in Figs. 11 and 12 the pistons instead of being mounted to reciprocate one within the other are mounted to reciprocate in a pair of cylinders positioned with such angularityas to simulate to a certain extent the cooifset and re-oifset described above in connection with the preferred form shown in Figs. land 2. m the form shown in Figs. 11 and 12 the cylinders are indicated generally. at 50 and cylinder 50 being positioned at an angularity inclined to the left as shown in Fig. 12, and cylinder BI is positioned at an angularity inclined to the right as shown in Fig. ii. The angularity of cylinder ii is somewhat less than the angularity of the cylinder 50 and may in some instances be vertical if desired. Also as shown in Fig. 12 the bottom end of each of cylinders lill and ii is offset a slight distance to the right of the vertical line passing through the center of the crank shaft.

As shown in Fig. 11 a common combustion chamber 52 is provided to extend above the upper end of both of the pistons 53 and 54', there also being provided the intake valves 55 and exhaust valves 56, of which the appropriate number will be used to accommodate the number of cylinders in the engine. In the event that only two cylinders are used it will be necessary tohave only one inlet valve and one exhaust valve because of the combustion chamber being common to both pistons. Also as shown in Fig. 11 a spark plug 51 of any desired form will be used. In the form shown in Figs. 11 and 12 connecting'rod i8 is somewhat longer than connecting rod 59, but these connecting rods 58 and 59 are of nearer the same length than the connecting rods in the form illustrated in'Figs. 1 and 2. This arrangement of length of connecting rods in the form shown in Figs. 11 and 12 can be varied as desired for different effects. The lower ends of the connecting rods 58 and 59 are formed with suitable bearings 80 and ii respectively, which bearings cooperate with the crank pins 82 and 63 carried by the crank arms 64 and 65. The crank arms 64 and 85 are positioned a suitable distance apart to accommodate the bearings on the connecting rods, and there is also provided a space between said bearings to receive the enlarged portion 08, which if cast is formed integral with the crank pins and preferably extends in the form of a disk 61, which also is cast integral with the portion 86 and the crank pins 62 and 63, which crank pins are in turn integral with the crank arms 64 and 85 and the crank shaft.

This integral disk 61 serves as a counter-balance for the crank arms, crank pins and connecting rods, and also the portion 66 serves as a spacing element to properly space the bearings 60 and 6| in such manner asmay be required by the distance these connecting rods are apart which, as will be understood, will vary with the different diameters of cylinders, but disk 61 may be dispensed with in certain circumstances.

As shown in Fig. 12, the crank pin 62 is in advance of crank pin 83, the direction of rotation being as indicated by the arrow. As seen in Fig. 11, the leading crank pin 62 is actuated by the longer connecting rod 58 and piston 53 in cylinder 5|, the angularity of which is shown in Fig. 12 to be inclined to the left. The trailing crank pin 83 is actuated by the shorter connecting rod 59 and piston 54, the angularity of which piston is shown in Fig. 12 to be inclined to the right at the top but which, as stated above, may be vertical if desired. This arrangement of leading and trailing crank pins with the angularity, of!- sets, and other desired arrangements, will produce to a greater or less degree many of the results accomplished by the form of my invention shown in Figs. 1 and 2, but is not as much preferred in some respects as the form shown in Figs. 1 and 2. The form shown in Figs. 11 and 12 is included to afford protection on such matters as may be common between the two forms thus described. v

In the arrangement and operation of the parts herein disclosed, the offset of the lower ends of the connecting rods and crank pins- (Figs. 1 to 12) when observed and calculated at various stages in their paths about the axisof the crank shaft 9, will be found to amplify progressively the torque factors. This is partly due to the volumetric control in the combustion portion'of the cylinder by reason of the fractional displacement of the pistons (differently timed) as compared with the conventional type of single piston.

Considering the crank pins at upper dead center as shown in Figs. 1 and 6, and drawing a straight line in the plane of the paper connecting the axes of the offset crank pins, it will be seen that this line forms a flattened portion on the circle of the crank pin path. The significance of this is that it fractionates displacement of the working faces of the plural pistons. This effect occurs with varying degree at various different positions of the crank pins throughout the crank pin circle. Further this effects the compression ratio as well as the effective pressure in the power displacement during the first quadrant of the power stroke, and thereafter alternately dividing within the same unit of time to produce the Y altered lateral relations of connecting rods relatively to each other and together relatively to the axis of crank shaft axis 9, Fig. 1, as compared with a single piston and connecting rod of the conventional type.

While I have shown my invention in an upright or vertical position common to engines usually designated as a straight-in-line type, I wish it understood that with perhaps slight rearrangement of the essential parts the structure generally is applicable to what are called rotary, horizontal, V and W types of engines, compressors and the like. 7

Having now described my invention I claim:

1. Mechanism of the class described comprising two crank pins circumferentially spaced apart length. and a piston operatively connected to each of said connecting rods. I

2. In mechanism of the class described, a plurality of pistons, a connecting rod operatively connected to each of said pistons, a crank shaft, a crank pin operatively connected to each of said connecting rods, said crank pins being circumferentially spaced apart with relation to said crank shaft, a common compression chamber for said pistons, said pistons being mounted for reciprocal movement along paths, the longitudinal center line of movement of one piston being angularly displaced with relation to a longitudinal center line oi the path of movement of the other piston.

3. In mechanism of the class described, 9. cyl inder, a pair of pistons in said cylinder, one of said pistons being slidably mounted in the other, the path of movement of one piston forming an angle with relation to the path of movement of the other piston, a crank shaft, a pair of crank pins on said crank shaft, and a pair of connecting rods, each of said connecting rods connecting a piston with its crank pin.

4. In mechanism of the class described, 9. cylinder, a pair of pistons in said cylinder, one of said pistons being slidably mounted in the other, the path of movement of one piston forming an angle with relation to the path of movement of the other piston, a crank shaft, a pair of crank pins on said crank shaft, and a pair of connecting rods, each of said connecting rods connecting a piston with its crank pin, said crank pins being circumferentially offset from each other, and a compression chamber common to both of said pi o s.

5. In mechanism of the class described, a cylinder, a crank shaft, a composite piston made up of a plurality of pistons movable with relation to each other, a plurality of crank pins on said crank shaft, said crank pins having equal throws, a plurality of connecting rods each connecting a piston with a crank pin, said parts being so constructed and arranged that said pistons will coact one with the other so as to offset dead centers, each of said pistons having a wrist pin, said wrist pins being at all times vertically spaced apart.

6. In mechanism of the class described, a single cylinder, a crank shaft, a plurality of pistons in said single cylinder, said pistons being movable angularly with relation to each other, a

plurality of crank pins on said crank shaft, a

plurality of connecting rods each connecting a piston with a crank pin, said crank pins being circumferentially spaced apart, and said connecting rods being so arranged and so connected with the crank pins and pistons as to produce such a shift of pressure across dead centers as to produce accelerated turning effort and turbulence in a delimited unit of time.

7. In mechanism of the class described, a crank shaft having a plurality of circumferentially spaced crank pins, a plurality of pistons movable angularly with relation to each other, a plurality of connecting rods each connecting a piston and a crank pin, said connecting rods being of unequal length, diiferently timed and so disposed as to coact in different directions simultaneously.

8. In an internal combustion engine. a crank shaft having a pair of circumferentially spaced crank pins. 9. cylinder. a pair of pistons in said cylinder, one of said pistons being slidably mounted in the other, the longitudinal axis of one of said pistons forming an angle with the longitudinal axis of the other piston, a connecting rod for each of said pistons, the connecting rod for the inner piston being connected with the leading crank pin, and the connecting rod for the outer piston being connected to the trailing crank pin. I

9. In an internal combustion engine, a cylinder, a crank shaft, the longitudinal axis of the cylinder being laterally offset from the vertical plane of the crank shaft axis when the cylinder is held in a vertical position, a pair of circumferentially spaced crank pins, a pair of pistons one slidably mounted in the other, and a pair of connecting rods connecting the pistons with their respective crank pins.

10. In an internal combustion engine, a cylinder, a plurality of pistons one of which is slidably mounted relatively to another, a crank shaft, a pair of circumferentially spaced crank pins on said crank shaft, the longitudinal axis of one of said pistons forming an angle with relation to the longitudinal axis of another of said pistons, the composite piston made up of said plurality of pistons having obliquely inclined pressure receiving faces, each component piston being differently timed to agitate the fuel in the combustion chamber alternately in diflerent directions whereby to produce increased turbulence.

11. In a reciprocating engine having a crank shaft, a pair of circumferentialy spaced crank pins, connecting rods and a pair of pistons, a pair of cylinders mounted at an angle to each other whereby their pistons will be cross-sequently mounted on separate connecting rods, said connecting rods being of nearly equal lengths and differently timed, said cylinders being of nearly equal bore, the pressure receiving faces of the pistons being of nearly equal area, whereby to transform the dead center periods to accelerated movement in the direction of crank arm rotation.

12. In an engine, a cylinder, a crank shaft, a pair of circumferentially spaced crank pins, the longitudinal axis of the cylinder being at variance with a line perpendicular to the crank shaft axis, a composite piston in said cylinder, said piston comprising an outer piston formed with a longitudinal bore and an inner piston reciprocally mounted in said bore, the longitudinal axis of said bore being at an angle to the longitudinal axis of the cylinder, which latter axis is laterally oil'set from the vertical plane of the crank shaft axis when the cylinder is positioned vertically, the inner piston being connected with a connecting rod by a wrist pin which when the piston is near its outer limit of movement is oilset from the longitudinal axis of the cylinder in a direction toward said vertical plane of the crank shaft axis and in a direction opposite to the direction of rotation of the crank arm when passing through its near dead center, the lower end of the inner piston connecting rod being journaled on the leading crank pin and the lower end of the outer piston connecting rod being journaled on the trailing crank pin, said inner and outer pistons interacting to displace pressure volume at different rates throughout the whole of a cycle and further to convert dead center periods into torsionaily useful periods within a relative accelerated time limitation.

13. In mechanism oi the class described, a cylinder, a crank shaft, a pair of circumferentially spaced crank pins, a pair of pistons one reciprocally slidable in the other, a connecting rod for 16 each of said pistons, the connecting rod for the inner piston being joumaled on the leading crank pin, the connecting rod for the outer piston being journaled on the trailing crank pin, the longitudinal axis of the cylinder being laterally offset with relation to the crank shaft.

14. In mechanism of the class described, a cylinder, a crank shaft, a pair of circumferentially spaced crank pins, a pair of pistons one reciprocally slidable in the other, a connecting rod for each of said pistons, the connecting rod for the inner piston being journaled on the leading crank pin, the connecting rod for the outer piston being journaled on the trailing crank pin, the longitudinal axis of the cylinder being laterally oilfset with relation to the crank shaft, and the iongitudinal axis of the inner piston forming an angle with relation to the longitudinal axis of the outer piston.

15. In mechanism of the class described, a cylinder, a crank shaft, a pair of circumferentially spaced crank pins, a pair of pistons one reciprocally slidable in the other, a connecting rod for each of said pistons, the connecting rod for the inner piston being journaled on the leading crank pin, the connecting rod for the outer piston being journaled on the trailing crank pin, the longitudinal axis of the cylinder being laterally offset with relation to the crank shaft, and the longitudinal axis of the inner piston forming an angle with relation to the longitudinal axis of the outer piston, the angularly extending longitudinal axis of the inner piston inclining downwardly and toward the offset side of thecylinder.

16. In mechanism of the class described, a cylinder, a crank shaft, a pair of circumferentially spaced crank pins, a pair of pistons one reciprocally slidable in the other, a connecting rod for each of said pistons, the connecting rod for the inner piston being journaled on the leading crank pin, the connecting rod for the outer piston being journaled on the trailing crank pin, the longitudinal axis of the cylinder being laterally offset with relation to the crank shaft, the connecting rod for the inner piston being longer than the connecting rod for the outer piston.

17. In mechanism of the class described, a cylinder, a crank shaft, a pair of pistons one longitudinally slidable in the other, three crank pins on said crank shaft, two of said crank pins being in alignment longitudinally of the crank shaft but spaced apart, the third crank pin being between said two crank pins but circumferentially offsettherefrom, a connecting rod connected to the inner piston near itsupper end and journaled at its lower end to said third crank pin, a pair of connecting rods connected at their upper ends to the outer piston near its lower end, and journaled at their lower ends to said two crank pins respectively.

18. In mechanism of the class described, a cylinder, a crank shaft, a pair of pistons one longitudinally slidable in the other, three crank pins on said crank shaft, two of said crank pins being in alignment longitudinal of the crank shaft but spaced apart, the third crank pin being between said two crank pins but circumferentially offset therefrom, a connecting rod connected to the inner piston near its upper end and journaled at its lower end to .said third crank pin, a pair of connecting rods connected at their upper ends to the outer piston near its lower end and journaled at their lower ends to said two crank pins respectively, the longitudinal axis of said cylinder being laterally oifset with relation to said crank shaft.

19. In mechanism of the class described, a pair of pistons movable angularly with relation to each other, a single pressure chamber for both pistons, a crank shaft, a pair of circumferentially spaced crank pins on said crank shaft, 9. pair of connecting rods, said pistons having separate pressure receiving faces of approximately equal cross-sectional area so disposed that the center of pressure, on the composite working faces of the pistons is guided in a slanting direction.

GEORGE G. KITZEMAN. 

